HELP!

[LFG List]

I am trying to learn enough about LFG to understand and apply it myself,
as well as being able to explain it effectively to my students.  Most of
them are from a GB background (me too), or possibly a more structuralist
tradition.  It may well be the case that my GB viewpoint is encumbering
me with presuppositions that are hindering my understanding, of course,
and it is certainly the case that my questions are very basic.  But when
a student asks "How did you come up with that?!" I'd like to be able to
tell them!

My first problem has to do with functional-structure.  Here's how I think
f-structure for a given sentence is developed, please correct me if I'm
wrong.  A typical verb might be characterized in f-structure along the
lines of the following, taking a classical example (I know where the up
arrows go, but I don't know how to represent them in this text format):
	'HAND<(^ SUBJ)(^ OBJ)(^ OBJ2)>' 
It seems, however, that there is a representation more basic, namely
one in which the entry seems to correspond to the theta grids of GB,
along the lines of the following (I don't know if capitals should be
used here to indicate a semantic notion or not):
	hand (agent) (goal) (theme)
It is principles of grammatical function assignment that then associate
these (universal) thematic roles with the (universal) grammatical functions.
I am thinking that because this mapping is well defined, it is rarely
referred to, and the representations using grammatical functions is used
instead as a sort of shorthand.  Is this correct?  (One of the major
important insights of the theory, of course, is that such grammatical
functions are universal, with the details manifested in language-specific
ways in different languages.  I have to leave discussion and clarification
of this point to a later inquiry.)

OK, so is it possible to take the position also that it is the verb's lexical
entry that constrains the remainder of the f-structure for a given sentence?
I.e., given that this instance of HAND requires SUBJ,OBJ, and OBJ2 to be
present, those grammatical functions must also appear in the f-structure of
the sentence, specific manifestations selected arbitrarily in any given
instance (as is the verb itself)?  I.e., the principles of Completeness and
Coherence insure that the proper number and type of arguments is associated
with the predicate (not unlike the Theta Criterion, it seems).  However,
some questions persist:  Is it required that SUBJ, OBJ, OBJ2 be NPs?  Where
is that information found?  Do NPs and other constructions have their own
c-structure rules?  I would expect so, but I have not come across any
examples in my reading.

If I am correct, the development of the f-structure for a given sentence may
be characterized as a progression along the lines of the following:
	predicate and its thematic roles selected
	thematic roles associated with grammatical functions on universal
		grounds
	grammatical functions established within f-structure and "filled in"
		appropriately

Your help is very much appreciated.  I realize that this is so basic that
all of you on the list could respond and a lot of time would be wasted by
the redundancy.  I don't know what to do; perhaps you have a designated
guide?!

Don Burquest, University of Texas at Arlington